U.S. patent application number 10/425289 was filed with the patent office on 2004-04-08 for process for treatment of organic wastes.
Invention is credited to Bhawalkar, Uday S., Pattanaik, Biplab R., Shankar, Hariharan S..
Application Number | 20040065610 10/425289 |
Document ID | / |
Family ID | 29272061 |
Filed Date | 2004-04-08 |
United States Patent
Application |
20040065610 |
Kind Code |
A1 |
Shankar, Hariharan S. ; et
al. |
April 8, 2004 |
Process for treatment of organic wastes
Abstract
A process for conversion of organic wastes into biofertilizers
such as soil conditioning agents of fertilizer grade, culture grade
and soil grade is provided. Also provided is a process for
conversion of organic wastes into material for converting waste
water into reusable water. The invention provides methods for
conversion of organic solid wastes to biofertilizers and reusable
water in the presence of a geophagus earthworm Pheretima elongata
culure to produce a variety of valuable soil conditioning products
and reusable water.
Inventors: |
Shankar, Hariharan S.;
(Mumbai, IN) ; Pattanaik, Biplab R.; (Cuttack,
IN) ; Bhawalkar, Uday S.; (Pune, IN) |
Correspondence
Address: |
Shantanu Basu
Morrison & Foerster LLP
755 Page Mill Road
Palo Alto
CA
94304
US
|
Family ID: |
29272061 |
Appl. No.: |
10/425289 |
Filed: |
April 28, 2003 |
Current U.S.
Class: |
210/602 |
Current CPC
Class: |
C05F 17/05 20200101;
Y02W 30/40 20150501; C05F 17/40 20200101; C02F 3/327 20130101; Y02W
10/10 20150501; Y02P 20/145 20151101; Y02W 30/43 20150501; Y02W
10/18 20150501 |
Class at
Publication: |
210/602 |
International
Class: |
C02F 003/32 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 26, 2002 |
IN |
383/MUM/2002 |
Apr 26, 2002 |
IN |
384/MUM/2002 |
Claims
What is claimed is:
1. A process for treating organic waste comprising: providing a
material comprising organic waste; contacting said material with a
geophagus earthworm Pheretima elongata culture; and providing
conditions for conversion of said material by said geophagus
earthworm Pheretima elongata culture.
2. The process for treating organic waste of claim 1, wherein said
material is converted to a biofertilizer.
3. The process for treating organic waste of claim 1, wherein said
material is a waste water that is converted to a reusable
water.
4. The process for treating organic waste of claim 1, wherein said
geophagus earthworm Pheretima elongata culture is provided as a
biofilter medium.
5. The process for treating organic waste of claim 4, wherein said
biofilter medium further comprises (a) a bacteria culture; and
optionally, (b) a mineral source.
6. The process for treating organic waste of claim 5, wherein said
mineral source is used in amounts up to 200% (w/w) and comprises
silica (between about 25-30% Si), alumina (between about 6-8% Al),
iron (between about 1-6% Fe), calcium (between about 2-10%),
magnesium (between about 1-3%), potassium (between about 2-8%),
phosporous (between about 0.003-0.1%) and mineral based
micronutrients.
7. The process for treating organic waste of claim 6, wherein said
micronutrients comprise micro quantities of Zinc (Zn) and
Molybdenum (Mo).
8. The process for treating organic waste of claim 4, further
comprising: adding a mineral additive to said biofilter media.
9. The process for treating organic waste of claim 8, wherein said
mineral additive comprises: rock powder of 0.3-0.6 kg/kg organic
waste; natural phosphate powder (0.02-0.05 kg/kg organic waste);
and soil (0.05-0.2 kg/kg organic waste).
10. The process for treating organic waste of claim 10, wherein
said rock powder is selected from the group consisting of a primary
rock powder and a weathered rock powder.
11. The process for treating organic waste of claim 8, wherein said
mineral additive comprises lime and ferric sulphate.
12. The process of treating organic waste according to claim 5,
wherein said organic waste is selected from the group consisting of
municipal waste, domestic waste, agricultural waste, industrial
waste, hospital waste, animal and human excreta, vegetable and
fruit residue, cooked food, protein residue, leaf and straw litter,
slaughter waste and combinations thereof.
13. A process for preparing a geophagus earthworm Pheretima
elongata culture comprising: providing the geophagus earthworm
Pheretima elongata; providing a covered green space; adding said
geophagus earthworm Pheretima elongata to said green space; and
providing conditions for said geophagus earthworm Pheretima
elongata culture to develop.
14. The process of preparing geophagus earthworm culture of claim
13, further comprising: harvesting said geophagus earthworm
Pheretima elongata culture by sieving as powder of less than about
500 micron size.
15. A process for preparing a bacteria culture comprising:
providing excreta from ruminant animals, wherein said excreta
comprise bacteria; mixing said excreta with a mineral source;
developing said bacteria culture with a geophagus earthworm
Pheretima elongata culture according to claim 13, in a green space
for about 4-6 weeks.
16. The process of preparing bacteria culture of claim 15, further
comprising: harvesting said bacteria culture by sieving as a powder
of less than 500 micron size.
17. The process of preparing bacteria culture of claim 15, wherein
said mineral source comprises silica (between about 25-30% Si),
alumina (between about 6-8% Al), iron (between about 1-6%), calcium
(between about 2-10%), magnesium (between about 1-3%), potassium
(between about 2-8%), phosporous (between about 0.003-0.1%) and
mineral based micronutrients.
18. The process of preparing bacteria culture of claim 17, wherein
said micronutrients comprise micro quantities of Zinc (Zn) and
Molybdenum (Mo).
19. The process of preparing bacteria culture of claim 15, wherein
said ruminant animals are fed on a cellulose based feed.
20. A process of developing a green space comprising: providing
organics to a soil surface, said organics between about 20 and 30
g/m.sup.2 of the soil; maintaining a moisture level between about
30 and 40% in said green space; and adding between about 5 and 10
g/m.sup.2 per day of a mineral source.
21. The process of developing a green space of claim 20, wherein
said mineral source comprises silica (between about 25-30% Si),
alumina (between about 6-8% Al), Iron (between about 1-6%), calcium
(between about 2-10%), Magnesium (between about 1-3%), Potassium
(between about 2-8%), Phosporous (between about 0.003-0.1%) and
mineral based micronutrients.
22. The process of developing a green space of claim 21, wherein
said micronutrients comprise micro quantities of Zinc (Zn) and
Molybdenum (Mo).
23. The process of developing a green space of claim 20, wherein
said organics comprise excreta of ruminant animals.
24. The process of developing a green space of claim 23, wherein
said ruminant animals are fed on a cellulose-based feed.
25. The process for treating organic waste of claim 5, wherein a
culture grade of said biofertilizer is prepared by a method
comprising: combining said mineral source in amount of between
about 0.3-0.6 kg/kg organic waste, a bacteria culture according to
claim 15 in amount of about 0.01 kg/kg organic waste, and a soil
processed by the geophagus earthworm Pheretima elongata culture in
amount of about 0.05-0.1 kg/kg organic waste to form a mixture;
loading organics in amount of about 0.1-0.5 kg/m.sup.2 per day to
said mixture; maintaining 30-40% moisture during said process in
said mixture; and incubating said mixture between about 180 and 220
days until said culture grade of said biofertilizer contains 5-10%
organics, 70-85% minerals and 10-15% moisture enriched with said
bacteria culture and said geophagus earthworm Pheretima elongata
culture.
26. The process for treating organic waste of claim 5, wherein a
fertilizer grade of said biofertilizer is prepared by a method
comprising: combining said mineral source in amount of between
about 0.3-0.6 kg/kg organic waste, a bacteria culture according to
claim 20 in amount of between about 0.01 kg/kg organic waste, and a
soil processed by geophagus earthworm Pheretima elongata culture in
amount of between about 0.05-0.1 kg/kg organic waste to form a
mixture; loading organics in amount of 1-5 kg/m.sup.2 per day to
said mixture; maintaining 30-40% moisture during said process in
said mixture; and incubating said mixture between about 56 and 70
days until said fertilizer grade of said biofertilizer contains
20-30% organics, 50-65% minerals and 15-20% moisture enriched with
said bacteria culture and said geophagus earthworm Pheretima
elongata culture.
27. The process for treating organic waste of claim 5, wherein a
soil grade of said biofertilizer is prepared by a method
comprising: combining said mineral source in amount of about 1.0
kg/kg organic waste, a bacteria culture according to claim 20 in
amount of about 0.01 kg/kg organic waste, and a soil processed by
geophagus earthworm Pheretima elongata culture in amount of between
about 0.05-0.1 kg/kg organic waste to form a mixture; loading
organics in amount of between about 1-5 kg/m.sup.2 per day to said
mixture; maintaining between about 30-40% moisture during said
process in said mixture, and incubating said mixture for a period
of time until said soil grade of said biofertilizer grade contains
10-15% organics, 65-75% minerals, 10-15% moisture enriched with
said bacteria culture and said geophagus earthworm Pheretima
elongata culture.
28. The process of treating organic waste of claim 27, wherein said
organics are excreta of ruminant animals.
29. The process of treating organic waste of claim 28, wherein said
period of time between about 7 and 14 days.
30. The process of treating organic waste of claim 27, wherein said
organics include finely divided organic food waste.
31. The process for treating organic waste of claim 30, wherein
said period of time is between about 28 and 35 days.
32. The process for treating organic waste of claim 5, wherein
creating said biofertilizer further comprises: combining said
mineral source in amount of 0.3-0.6 kg/kg organic waste, bacteria
culture according to claim 20 in amount of about 0.1 kg/kg organic
waste, and a soil processed by geophagous earthworm culture in
amount of between about 0.3-0.6 kg/kg organic waste to form a
mixture; loading organics to said mixture, said organics being
hospital organic waste; incubating said mixture between about 10
and 14 months; maintaining 30-40% moisture during said process in
said mixture; burning said mixture with said leaf and straw litter;
and recovering said biofertilizer after incubating said mixture for
28 weeks.
33. An organic waste treatment system comprising: (a) a biofilter
media comprising a geophagus earthworm Pheretima elongata culture;
(b) a bacteria culture; and optionally (c) a mineral source.
34. The organic waste treatment system of claim 33, further
comprising a mineral additive.
35. The organic waste treatment system of claim 34, said mineral
additive comprising: rock powder of 0.3-0.6 kg/kg organic waste;
natural phosphate powder (0.02-0.05 kg/kg organic waste); and soil
(0.05-0.2 kg/kg organic waste).
36. The organic waste treatment system of claim 35, wherein said
rock powder is selected from the group consisting of (a) a primary
rock powder and (b) a weathered rock powder.
37. The organic waste treatment system of claim 34, wherein said
mineral additive comprises lime and ferric sulphate, said mineral
additive assisting in reducing phosphate content.
38. The organic waste treatment system of claim 33, wherein said
system achieves removal rate constants for BOD (up to 0.5/hr), COD
(up to 0.4/day), ammonia (up to 1.0/hr), nitrate nitrogen (up to
0.1/hr), suspended solids (up to 0.5/hr), bacteria (up to 1.0/hr)
with hydraulic loading of 0.02 to 0.1 cm/sq. m per hr.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority of Indian Patent
application no. 383/MUM/2002 entitled "Process for Waste Water
Renovation," filed Apr. 26, 2002, and Indian application
No.384/MUM/2002 entitled "Process for Treatment of Organic Wastes,"
filed Apr. 26, 2002, by the same inventors. Both applications are
expressly incorporated herein by reference in their entirety.
TECHNICAL FIELD OF THE INVENTION
[0002] This invention relates to a process for conversion of
organic wastes into biofertilizers such as soil conditioning agents
of fertilizer grade, culture grade and soil grade and reusable
water. In particular, the invention relates to a process for
conversion of organic solid wastes to biofertilizers and reusable
water in the presence of selective geophagus earthworms Pheretima
elongata culture to produce variety of valuable soil conditioning
products and reusable water by way of a simple and cost effective
process.
BACKGROUND OF THE INVENTION
[0003] Human and animal habitations generate large quantities of
wastes. The organic fraction of these wastes often accumulate in
the neighborhood of habitations and their decomposition products
affect detrimentally the quality of soil, water and air. Meanwhile,
the demand for water has gone up and the need to renovate and reuse
water has become imperative. In developing countries existing
technologies for wastewater renovation are viable only in very
large-scale operations and so cost of operation becomes prohibitive
and lead to improper functioning and maintenance of plants
(Arceivala, S. J., Wastewater Treatment for Pollution control, TMH
publications New Delhi, India, 1998). Even the treated water in
many cases breed mosquitoes thereby compounding the problem.
[0004] Many technologies are available to deal with organic wastes
but most of these are energy intensive. Sanitary land filling is
becoming unviable due to non-availability of landfill space. In
biogas technology investments are large and subsequent liquid
effluents consume much energy for disposal and solid product from
such processes having low energy value for soil have limited market
as fertilizer. Most current technologies face problems of acidity,
culture fatalities and problems of process waste disposal.
Composting has been practiced for over 50 years. However in the
composting process bioenergy of the organic waste is lost and
therefore the product retains very little energy for use in soil.
In view of energy cost of composting operation, low value and low
yield of product, the technology becomes useful if disposal is the
objective. Organic waste conversion to biomass briquettes is a
useful technology but the energy cost of drying and briquetting is
high and hence such technology is also unviable in many cases.
[0005] Several technologies are available for treatment of organic
liquid waste containing chemical oxygen demand (COD), biochemical
oxygen demand (BOD), nitrogen, phosphorous, suspended solids,
bacteria, color, odor etc. The presence of these pollutants in
water is a form of toxicity and should therefore be substantially
removed. Activated Sludge, Trickling filter, and Oxidation Ponds
are examples of technologies currently in operation. All these
technologies are energy intensive and viable only in very large
scale. They produce residues whose disposal can create problems.
Treated water is generally not fish compatible and such water
discharged into drinking water sources endanger lives of dependent
population (Bhawalkar, U.S., "Vermiculture Bioconversion of Organic
Residues", Ph.D. Thesis, Dept. of Chemical Engineering, IIT Bombay,
1996; Pattanaik B. R., "Processing of Wastewaters in Soil Filters",
Ph.D. Thesis, Dept. of Chemical Engineering, IIT Bombay, 2000).
Land treatment of wastewater has been known for long. Here
intermittent hydraulic loading of 0.001 m.sup.3/m.sup.2 per hr. is
permissible and treated water is not easy to recover for reuse.
Root zone treatment technology is similar to land treatment methods
and have similar requirement and features (Nivens, Jr., U.S. Pat.
No. 6,264,838, "Onsite Wastewater Recycling System"). Constructed
wetland treatment technology has been in practice in many areas. In
this case wetland--rock--aquatic ecology is engaged wherein
subsurface flow brings about treatment. Hydraulic loading of
0.001-0.005 m.sup.3/m.sup.2.hr is observed (Behrends, U.S. Pat. No.
5,863,433, "Reciprocating Subsurface Flow, Constructed wetland for
improving Wastewater Treatment").
[0006] Use of surface dwelling redworm Eisenia foetida in
vermifilters and Vermicomposting is known (Lee, K. E.,
Earthworms--Their ecology and relationship with soils & land
use, Academic Press, NY (1985)). However, there are major drawbacks
of such processes and formulations leading to low yield of
vermicompost. Moreover, it requires well-macerated excreta,
preferably animal excreta, containing 1 percent or more protein
nitrogen and 70 percent moisture. Also, there are problems of
maintaining them in the filter. This is because they cannot live in
their own excreta and as conditions arising from accumulation of
waste products become adverse they migrate away. (Bhawalkar,
"Vermiculture Bioconversion of Organic Residues", Ph per day.
Thesis, Dept. of Chemical Engineering, IIT Bombay, 1996.; Pattanaik
B. R., "Processing of Wastewaters in Soil Filters", Ph per day.
Thesis, Dept. of Chemical Engineering, IIT Bombay, 2000) In order
to prevent this migration converted material is to be separated and
fresh material is to be added to the process. This leads to low
loading rates thereby requiring large space for the vermicomposting
process. Culture replacement is also necessary. In view of the
generated acidic environment abnormal bio indicators of acidic
environment do appear and the use of other chemical pest control
measures become necessary. When the acidity becomes very high it
becomes essential to unearth the entire space and prepare the place
afresh leading to long turnover times, loss of productivity, etc.
Such redworm cultures not being native to healthy soils their
disposal becomes problematic. Other issues related to the use of
Eisenia foetida (all surface dwelling varieties) are sudden loss of
culture and pest incidence. (Bhawalkar U.S., Vermiculture
bioconversion of Organic Residues, Ph per day. thesis, IIT Bombay
1996; Pattanaik, B. R., Waste Water Processing in Soil Filters, Ph
per day. thesis, IIT Bombay, 2000). In general, available
technologies do not use soil system because they tend to choke and
become non-functional.
SUMMARY OF THE INVENTION
[0007] The present invention is directed to providing a process and
a system for large scale processing of organic wastes including
animal/human faeces using green technologies for organic waste
conversion to biofertilizer and reusable water, herein referred to
as Soil Biotechnology (SBT), without formation of objectionable
process wastes thereby eliminating common operating problems of
clogging, interruptions and waste disposal.
[0008] According to one aspect of the invention there is provided a
process for treating organic waste for manufacture of biofertilizer
and substantially non-toxic reusable water comprising: i)
processing the organic liquid waste in a biofilter media comprising
culture of geophagus earthworms Pheretima elongata, soil and
bacterial cultures as defined herein with or without other mineral
additive thereby providing substantially non-toxic reusable water;
and ii) processing the organic solid waste selectively in the
presence of cultures of geophagus earthworm Pheretima elongata in
combination with bacterial cultures such as defined herein and a
mineral source under controlled moisture content to provide a
biofertilizer.
[0009] According to another aspect of the invention there is
provided a process for producing biofilter media comprising
earthworm culture comprising: a) collecting the geophagus earthworm
Pheretima elongata from its natural habitat; b) developing a
covered green space on the soil by providing 20-30 g/m.sup.2 per
day organics such as herein defined, ii) maintaining moisture at
about 30-40%, and iii) adding the preferred mineral powder at less
than 1000 micron@5-10 g/m.sup.2 per day; and c) harvesting the
culture after appropriate period of time (preferably following a
high rainfall period, such as monsoon season) as sieved powder. The
powder obtained is used as a source of earthworm culture. The
sieved powder could be made of particles less than 500 microns in
size.
[0010] According to another aspect of the invention there is
provided a process for producing biofilter media comprising
bacterial culture comprising: (a) developing the appropriate
geophagus earthworm culture Pheretima elongata in a green space for
4-6 weeks by providing i) 20-30 g/m.sup.2 per day organics such as
hereindefined ii) moisture about 30-40% iii) preferred mineral
powder of appropriate size (about less than 1000 micron)@5-10
g/m.sup.2 per day; and (b) maintaining the mix above under
conditions for developing the cultures and harvesting the culture
as a sieved powder for use as a source of bacterial culture. The
culture could be sieved to about 500 micron size.
[0011] In accordance with the general process of this invention,
the single stage SBT process basically involves: (i) preparation of
the geophagus earthworms culture Pheretima elongata and preparation
of bacterial culture; (ii) preparation of the soil media to contain
the geophagus earthworms Pheretima elongata; (iii) construction of
an under drain first tank and a collection tank herein referred to
as second tank; (iv) layering of the media over the first tank; (v)
percolation of the organic waste through the layered media; (vi)
collection of the treated water in the second tank; (vii)
recirculation of the treated water to achieve the desired quality;
and (viii) using bioindicators to monitor the reformed water at
various stages of the process.
[0012] In one of the aspect of the invention mineral additive such
as primary mineral powder or weathered mineral powder or iron-rich
mineral powder of specified particle sizes and composition are
added into the organic waste to be treated.
[0013] According to one aspect of the invention there is provided a
biofiltration system for carrying out the process of treating
organic liquid waste to provide substantially non-toxic reusable
water comprising: i) a biofilter media comprising one or more
filter media selectively comprising of anyone or more of culture of
geophagus earthworm, bacterial cultures, soil with or without
mineral additive; and ii) organic wastewater for processing through
said biofilter in one stage or multiple stages and collect/supply
the water thus processed substantially free of toxic content.
[0014] In another aspect of the invention, a multi stage process of
organic waste renovation is carried out in a bio-tower wherein
several single stage SBT processes are sequentially integrated.
[0015] One aspect of the invention provides a process for
renovation of water from organic wastes--an integrated process
combining Geophagous earthworms with potent bacterial cultures,
minerals, water from organic wastes and soil.
[0016] Another aspect of the invention provides a process for easy
removal of suspended solids without use of energy and to recover
these solids as good quality fertilizer.
[0017] In another aspect of the invention, a multi stage process of
the organic waste renovation is carried out in a bio tower wherein
several single stage SBT processes are integrated with the option
to re-circulate the treated water from any stage to any other stage
as desired.
[0018] Another aspect of the invention provides a process wherein
bacterial selection interaction is nurtured via earthworm culture
so as to obtain a stable system despite large variation in input
load.
[0019] Another aspect of the invention provides an engineered
system for removal of nitrates and phosphates in water from organic
wastes.
[0020] Another aspect of the invention provides a process for
renovation at higher hydraulic loading rates.
[0021] Another aspect of the invention provides Biotower technology
using the SBT system for producing reusable water and save on space
wherein very high removal efficiencies are achieved.
[0022] Another aspect of the invention provides a technology for
non-chemical cleaning of swimming pool waters.
[0023] Another aspect of the invention provides a process for
renovation of water from organic wastes to fish compatible quality
so that water bodies viz. lakes and rivers afflicted by pollution
can be restored to health.
[0024] In another aspect of this invention the SBT process may be
implemented in any existing conventional activated sludge plants
and their like.
[0025] In another aspect of this invention the SBT process may be
implemented in any existing conventional oxidation ponds and their
like.
[0026] The process described herein removes one or more of
pollutants viz. BOD, COD, ammonium nitrogen, nitrate nitrogen,
suspended solids, phosphate, odor, colour, bacteria while
substantially increasing dissolved oxygen and producing fish
compatible renovated water and all this in a single integrated bed
without producing sludge.
[0027] Another aspect of the invention is a process for the
manufacture of effective fertilizer grade, culture grade and soil
grade SBT products from organic wastes in the presence of selective
species, which would facilitate such conversion without any
environmental problems.
[0028] Another aspect of the invention provides a process with high
oxygen transfer rates so as to ensure aerobic environment and have
high removal of BOD, COD and NH.sub.4--N and pathogens.
[0029] Yet another aspect of the invention provides a process for
manufacture of effective SBT products from organic wastes using
selective organisms that can operate at high rates without
requiring extensive field area to carry out such process.
[0030] Yet another objective of the invention is to provide for the
process of organic waste management that can be easily set up and
run with minimum cost, operational constraints and with maximal
operational advantages.
[0031] Yet Another aspect of the invention provides for process for
organic waste conversion, which would achieve high bioenergy
recovery efficiency.
[0032] Yet Another aspect of the invention provides a simple and
cost effective process for organic waste conversion to produce SBT
products in high yields.
[0033] Yet it is another object of the invention to produce pest
resistant SBT products with high activity and shelf-life.
[0034] According to another aspect of the present invention there
is provided a process for the manufacture of biofertilizer from
organic waste comprising: providing a culture media comprising
geophagus earthworm culture Pheretima elongata in a green space
including bacterial culture as herein defined, moisture and a
mineral source; processing the organic waste in the presence of
said culture media under controlled moisture content to obtain the
biofertilizer; and sieving to obtain the product of desired
particle size.
[0035] According to another aspect of the present invention there
is provided a process for the manufacture of biofertilizer from
organic waste comprising: (i) providing (a) the mineral additives;
(b) natural phosphate powder; (c) soil; and (d) bacterial culture;
and (ii) processing the mix of (i) above with organic waste in a
geophagus earthworm culture green space for sufficient period under
controlled moisture content to thereby obtain the desired
biofertilizer.
[0036] According to another aspect of the present invention there
is provided a process for the manufacture of biofertilizer from
organic waste comprising: providing a system of ridges and troughs;
providing a culture media comprising geophagus earthworm culture
Pheretima elongata as a green space including bacterial culture,
moisture and a mineral source in said ridges having green plants to
house said culture; and processing the organic waste in said system
under controlled moisture content to obtain the biofertilizer in
the presence of said culture media.
[0037] In one aspect of the invention an organic waste treatment
system is provided, the system comprising: a material comprising
organic waste; and a biofilter media comprising a geophagus
earthworm Pheretima elongata culture, a bacteria culture, and
optionally a mineral source.
[0038] The organic waste treatment system may comprise at least one
trough with a ridge, the trough to receive and hold the biofilter
media and the organic waste. In one embodiment, depth of the trough
is between about 1-3 m.
[0039] In one embodiment, the organic waste treatment system
comprises at least one first tank to receive and hold the biofilter
media and the organic waste, the first tank having a first pipe to
allow draining of the reusable water from the first tank. In one
embodiment, the first pipe is located substantially towards bottom
of the first tank.
[0040] In one embodiment, the organic waste treatment system
further comprises a second tank to receive and collect the reusable
water, the second tank connected to the first tank by the first
pipe, the first pipe allowing the reusable water to flow from the
first tank to the second tank.
[0041] In one embodiment, the first tank further includes a bottom
surface, the bottom surface having a slope of {fraction (1/100)}
gradient, the bottom surface being impervious.
[0042] In one embodiment of the organic waste treatment system the
first tank further holds at least one layer of a percolation media,
the percolation media spread as a layer across the bottom surface
of the first tank, the biofilter media spread as a layer on top of
the percolation media in the first tank, the percolation media
allowing percolation of the organic waste through the percolation
media, the percolation through the percolation media progressively
converting the organic waste.
[0043] In one embodiment, a biofiltration system comprises the
first tank further includes a second pipe to recirculate processed
water for further processing to obtain the processed water of
desired quality.
[0044] In one embodiment, the percolation media comprises a layer
of river sand, size of the river sand between about 2 and 3 mm,
thickness of the layer of river sand between about 5 and 10 mm. In
another embodiment, the percolation media further comprises a layer
of grit, size of the particles of grit between about 5 and 10 mm,
thickness of the layer of grit at 100 mm. In another embodiment,
the percolation media further comprises a layer of thick stone,
size of the thick stones between about 25 and 50 mm, thickness of
the layer of thick stone about 100 mm. In another embodiment, the
percolation media further comprises a layer of large boulders, size
of the large boulders between about 100 and 200 mm, thickness of
the layer of large boulder at 250 mm.
[0045] In one embodiment, the plurality of layers of percolation
media are arranged in progressively increasing size of particles in
each layer with smallest size particle layer at top and largest
size particle layer at bottom of the first tank.
[0046] In one embodiment, the organic waste treatment system is
adapted to run in batch mode of operation. In one embodiment, the
organic waste treatment system is adapted to run in continuous mode
of operation.
[0047] In one embodiment, the organic waste treatment system
comprises a plurality of first tanks to receive and hold the
biofilter media and the organic waste, the plurality of first tanks
connected to each other by plurality of second pipes, the plurality
of second pipes recirculating the processed water through the first
tanks to further process the reusable water to obtain the reusable
water of desired quality.
[0048] In one embodiment, the biofiltration system further includes
plurality of bioindicators to monitor quality of processing of the
organic waste at various stages of processing.
[0049] In one embodiment, the biofiltration system achieves a
removal rate constant for BOD (up to 0.5/hr), COD (up to 0.4/day),
ammonia (up to 1.0/hr), nitrate nitrogen (up to 0.1/hr), suspended
solids (up to 0.5/hr), bacteria (up to 1.0/hr) with hydraulic
loading of 0.02 to 0.1 cm/sq. m per hr.
BRIEF DESCRIPTION OF THE FIGURES
[0050] FIG. 1 shows the schematics of a biofilter operation.
[0051] FIG. 2 shows details for filling a biofilter.
[0052] FIG. 3 shows the schematics of a biotower.
DETAILED DESCRIPTION OF THE INVENTION
[0053] It has been surprisingly found by way of the present
invention that effective soil conditioning agents of fertilizer
grade, culture grade and soil grade SBT products and effective
renovation of water from organic waste can be achieved by way of
conversion of organic waste to environmentally friendly products
when such conversion is carried out selectively in the presence of
cultures of the geophagus earthworm Pheretima elongata in
combination with bacterial cultures, selective mineral source and
soil.
[0054] In accordance of this invention the process involves i)
preparation of cultures of geophagus earthworm Pheretima elongata
in combination with bacterial cultures; ii) In case of the water
processing system, an additional step of preparation of the media
is involved and iii) Using the above, solid waste or liquid waste
is appropriately treated.
[0055] Thus according to one aspect of the invention there is
provided a process for treating organic waste for manufacture of
biofertilizer and substantially non-toxic reusable water
comprising: processing the organic waste in a biofilter media
comprising a culture of the geophagus earthworm Pheretima elongata,
soil and bacterial cultures such as hereindefined with or without
other mineral additives thereby providing substantially non-toxic
reusable water; and processing the organic waste selectively in the
presence of cultures of geophagus earthworm Pheretima elongata in
combination with bacterial cultures such as herein defined and
mineral source under controlled moisture content to thereby provide
biofertilizer.
[0056] An appropriate geophagus earthworm culture Pheretima
elongata is provided. The culture is developed in a covered green
space by providing 20-30 gm/m.sup.2 per day of organics such as
ruminant animal dung which contains potent bacterial culture, or
straw and leaf litter, moisture 30-40 percent and preferred mineral
source powder of appropriate size at 5-10 g/m.sup.2 per day. The
culture is harvested for use as source culture of geophagus
earthworms. This culture can be further powdered and sieved to
about 500 micron size.
[0057] An appropriate bacterial culture is developed in a geophagus
earthworm cultured green space provided with 20-30 gm/m.sup.2 per
day organics such as excreta of ruminant animals, preferably cows,
buffaloes, bullocks, sheep, goats fed primarily on cellulosic
residue, moisture about 30-40%, and preferred mineral powder at
about 5-10 gm/m.sup.2 per day. The culture is harvested for use as
source culture of bacteria. The culture can be further powdered and
sieved to about 1000 micron size.
[0058] In one embodiment of the invention, an appropriate
formulated soil media 0.3-0.4 m thick produced by combining animal
dung (15-50%), preferred mineral source of appropriate particle
size (50-85%), bacterial and earthworm culture all processed in a
green space for 7 days by maintaining 30-40% moisture is
provided.
[0059] Preferred mineral source can be added in amounts of up to
200% w/w selected from sources containing silica (25-30% Si),
alumina (6-8% Al), iron (1-6% Fe), Potassium (2-8%), Calcium
(2-10%), Magnesium (1-3%) Phosphorous (0.003-0.1%) and also
containing micronutrients.
[0060] Preferred mineral additive can comprise lime, and ferric
sulfate used to reduce the phosphates to desired levels. Mineral
additive can also be comprised of rock powder (0.3-0.6 kg/kg
organic waste), natural phosphate powder (0.02-0.05 kg/kg organic
waste) and soil (0.05-0.2 kg/kg organic waste). The rock powder can
be a primary rock powder or a weathered rock powder. The mineral
additive in combination with said biofilter media further
facilitates removal of suspended solids.
[0061] Biofertilizer as used herein refers to material comprising
micro-organisms which are able to perform biochemical functions
including, but not limited to, fixing atmospheric nitrogen or
solubilizing phosphorus, decomposing organic material and oxidizing
sulphur in the soil. On application, a biofertilizer enhances the
growth of plants, increases yield and also improves soil
fertility.
[0062] BOD (biochemical oxygen demand) and COD (chemical oxygen
demand) of the organic liquid waste are measured as per procedures
specified in Standard Methods of Water and Waste-Water
Analysis.(APHA--Standard methods of Examination of water and waste
water, American Public Health Association, 18th edition,
Washington, D.C. (1992)).
[0063] Green space as used herein refers to an area that is created
or preserved for the purpose of growing living things.
[0064] Organic waste as used herein refers to material comprising
both organic solid waste and organic liquid waste.
[0065] Vermicompost as used herein refers to resulting worm-worked
material produced by earthworms.
[0066] I. Waste Water Renovation
[0067] This invention relates to a process for treating organic
liquid waste (wherein the organic liquid waste is contained in
municipal, domestic, agricultural, industrial waste containing
residues ranging from animal excreta, human excreta, vegetable and
fruit residues, straw and leaf litter, cooked food, protein
residues, slaughter waste, hospital organic waste and the like) for
providing substantially non-toxic reusable water involves
processing the organic liquid waste in a biofilter media comprising
culture of geophagus earthworms Pheretima elongata, soil and
bacterial cultures such as herein defined with or without other
mineral additive to provide substantially non-toxic reusable
water.
[0068] Provision for distribution of organic waste is made by
providing piped delivery to all parts of filter and distribution
parts to deliver water uniformly. An underdrain of large boulders
0.3-0.4 m thick, {fraction (1/100)}-{fraction (1/500)} gradient
sloping floor and a collection tank at a suitable location is also
provided.
[0069] Process control is achieved by adjusting loading rates,
addition of mineral powder so as to eliminate bioindicators of
abnormality viz., mosquitoes, rats, odor, plant disease, etc.
[0070] This approach brings about purification of organic waste
dependent on the process time, organic and hydraulic load.
[0071] In another embodiment of the invention mineral additives
powder are added to facilitate renovation.
[0072] According to another aspect of the invention there is
provided a biofiltration system for carrying out the process of
treating organic liquid waste to provide substantially non-toxic
reusable water comprising: biofilter media further comprising one
or more filter media selectively comprising of anyone or more of
culture of geophagus earthworm, bacterial cultures, soil with or
without mineral additive; means to process organic liquid waste
through said biofilter means in one stage or multiple stages and
collect/supply the water thus processed substantially free of toxic
content.
[0073] In another embodiment of the invention an SBT biotower for
the renovation of organic waste is provided wherein the process is
carried out in stages with each stage filled with typically
0.30-0.35 m of the media in the biotower. An embodiment of the
system involves up to 10 stages with each stage having a free board
of 1.8-2.0 m to maintain and also to carry out routine
operation.
[0074] In another embodiment of the invention the processed water
from any one of the stages in the bio tower may be re-circulated to
any other stage to achieve selective denitrification by contacting
the processed water with the layered stage that contains higher
amounts of BOD/COD.
[0075] In another embodiment of the invention, the process for
reforming organic liquid waste into reusable water achieves the
removal rate constant for BOD of upto 0.5/hr, COD for upto 0.4/day,
ammonia upto 1.0/hr, nitrate nitrogen of upto 0.1/hr, suspended
solids of upto 0.5/hr, bacteria of upto 1.0/hr and hydraulic
loading between about 0.02 to 0.1 cum/sq m per hour.
[0076] When soil systems are used for renovation of water from
organic waste, the system tends to choke. The role of the
earthworm--bacterial culture is to ensure uninterrupted operation.
This is reflected in the high values of rate constants for the
different solutes BOD, COD, Ammonium Nitrogen, Nitrate Nitrogen,
Suspended solids, Color, Odor, bacteria that need to be removed as
described in the examples.
[0077] The advantages of SBT processes are 1) land area saving can
be designed 2) process engages local land resources 3) energy
consumption is low as natural methods of oxygen supply is engaged
4) produces no residues for disposal which is a major issue in most
waste water treatment plants. 5) very stable against load
variations and 6) it is a green technology.
[0078] The unique features of this green technology are that the
BOD, COD, ammonium nitrogen, nitrate nitrogen, suspended solid,
colour, odour, bacteria, sufficient increase in dissolved oxygen,
no residues for disposal are all made possible in a single tank
constructed in the ground with its top open to atmosphere. In
addition use of SBT achieves space saving, high removal efficiency,
engages material that occurs locally, consumes no power for oxygen
delivery to the system, leaves no residues for disposal and is very
stable against shock loading. These advantages are unmatched by any
known technology.
[0079] II. Conversion of Solid Waste to Biofertilizer
[0080] The process for manufacture of biofertilizer from organic
solid waste (wherein the organics used are selected from municipal,
domestic, agricultural, hospital, industrial waste and residues
ranging from animal excreta, human excreta, vegetable and fruit
residues, straw and leaf litter, cooked food, protein residues,
slaughter waste, and the like) involves processing the organic
waste selectively in the presence of cultures of geophagus
earthworm Pheretima elongata in combination with bacterial cultures
such as herein defined and mineral source under controlled moisture
content.
[0081] According to one embodiment of the process of the invention
involves: (a) processing the organic waste, preferred mineral
source powder of a specific particle size range, soil, bacterial
culture source under controlled moisture in a geophagus earthworm
cultured green space for a required period; and (b) maintaining the
mix for sufficient period to effect conversion to desired
biofertilizer and sieving to a specified size range.
[0082] According to another aspect of the invention, yield of
biofertilizer product of the invention is typically 200-1500 kg/ton
raw waste depending on fertilizer grade, culture grade, soil grade
biofertilizer products but depends on nature of feed.
[0083] Preferably, by adjusting additives and batch time can
produce variety of products namely fertilizer to culture grade to
soil grade product. Typically products contain about 5-30%
organics, about 55-90% minerals, about 10-20% moisture and rich in
soil bacterial population and also containing geophagus earthworm
culture. Cycle time of 14 weeks is typical. Smaller cycle time
require more additives, mechanical shredding and intensive
management.
[0084] In another embodiment of the invention mineral additives
such as primary rock powder of about 0.3-0.6 kg per kg waste,
natural phosphate powder (about 0.02-0.05 kg./kg waste) and soil
(about 0.05-0.2 kg/kg waste), bacterial culture (about 0.01 kg/kg
waste) are added to enable organic conversion in a cultured green
space to fertilizer grade, culture grade, or soil grade
product.
[0085] Process control is achieved by adjusting loading rates,
moisture levels and by addition of mineral source so as to prevent
anaerobic environment and as well to eliminate bioindicators of
abnormality. Process monitoring is achieved by observing
bioindicators of abnormality viz. mosquitoes, rats, odour and plant
health.
[0086] In accordance with another embodiment for large scale
processing of organics the invention proposes the use of system of
ridges and troughs of height/depth 1-3 m to carry out the
conversion of organic waste for biofertilizer using the aforesaid
geophagus earthworm cultural green space.
[0087] The ridges can have the green plants that house the culture
engaged in the process. For different capacities length of ridges
and troughs can be adjusted. Higher loading as and when required
can be achieved by adjusting ridge dimensions. The costs are low
since energy inputs are low and thus would provide a cost-effective
process for manufacture of biofertilizer.
[0088] In yet another embodiment of the invention, culture of the
bacteria in the excreta of ruminant animals--e.g. cow, bullock,
buffalo, goat, sheep, etc. preferably fed on cellulose-based feed
are selected. The bacterial culture is further propagated by mixing
excreta with preferred mineral source and developed further for
about 4-6 weeks in geophagus earthworm cultured green space and
harvested for use in different locations to give the appropriate
bacterial culture.
[0089] In another embodiment of the invention the animal dung is
mixed with preferred mineral source and propagated further in a
geophagus earthworm culture green space for about 7-14 days to give
soil grade product.
[0090] In yet another embodiment of the invention hospital organic
waste can be disposed in geophagus earthworm cultured green space.
The space is organized to receive the hospital organic waste for
treatment using the invented process.
[0091] Fertilizer grade product obtained following the process of
the invention contains typically about 20-30% organics, about
50-65% minerals, and about 15-20% moisture. The culture grade
product contains about 5-10% organic, about 70-80% minerals, about
10-15% moisture. The soil grade product contains about 10-15%
organic, about 65-75% minerals and moisture about 10-15%. All the
products contain soil bacterial culture and geophagus earthworm
culture.
EXAMPLES
[0092] The inventions are now described and illustrated with the
following non-limiting examples. Examples 1-3 relate to waste water
renovation and Examples 4-7 relate to treatment of organic solid
waste.
Example 1
[0093] FIG. 1 shows a schematic of the system employed. A first
tank c1 25.0 m.times.10.0 m.times.1.0 m below ground was
constructed. A slope of {fraction (1/100)} gradient was provided on
the bottom surface of the first tank c1. The bottom surface was
made impervious. A second tank c2 for collection of renovated water
was provided. A pipe p1 connected the first tank c1 to the second
tank c2. A second pipe p2 connected the second tank c2 back to the
first tank c1 to recirculate the processed reusable water for
further processing. This is done to achieve higher quality of
reusable water. A biodindicator b1 is inserted at various stages of
processing to monitor the quality of the organic waste during the
various stages of the process. The filter fillings consisted of a
300-400 mm layer of formulated earthworm Pheretima elongata soil
media and 0.3-0.4 m under-drain of stone rubble of sizes varying
from 200 mm to 2 mm. The performance of filter operated in batch
mode is given in Table 1. Hydraulic loading of 0.02-0.06
m.sup.3/m.sup.2 per hour has been observed. Table 2 shows the
results of continuous operation. Biofilter filling details are
given in FIG. 2.
[0094] In another embodiment, a plurality of first tanks c1 are
engaged in the process of reforming the organic waste. Each of the
plurality of first tanks c1 are connected to each other by
plurality of first pipes p1. This helps in recirculating the water
through different tanks to get higher quality of reusable water.
The first tank is connected to second tank c2 by a second pipe p2.
A plurality of bioindicators b1 are inserted into various stages of
various tanks c1 to monitor the quality of the reusable water
during the various stages of the process.
[0095] Removal of potent pollutants such as BOD, COD, NH.sub.4--N,
NO.sub.3--N, phosphate (without using additive), suspended solids,
color, odor, bacteria can be achieved. Dissolved oxygen improves
significantly due to renovation. Fish inoculated in the filtrate
collection tank showed no fatality during operation and storage of
treated water, indicating fish compatible water is produced. Redox
potential of water improves substantially from 50 mV to 800 mV
indicating aerobic environment and pathogen destruction.
[0096] The typical values for the inlet (initial) and outlet
(final) organic waste are shown in Tables 1 & 2. Variations in
input do take place, but the desirable output water quality is
always obtained by adjusting the process operating conditions.
[0097] It is relevant to note that good phosphate removal is
observed without using additive. Wherever higher removal is needed
various additives e.g., lime, ferric sulfate, etc. can be used to
reduce the phosphates to desired levels.
[0098] The operation of this system under batch and continuous
modes reveal that earthworm culture Pheretima elongata ensures
clogging free operation, reproducible media reactivity and absence
of abnormal bioindicators and water output parameters indicating
excellent water quality. No fish fatality during the operation is a
unique feature of the process.
1TABLE 1 Batch Biofiltration results for Pheretima elongata
cultured soil filters Item Initial Final pH 7.4 7.0 NH.sub.4 mg/L
15 2 NO.sub.3 mg/L 43 3 Total N mg/L 21 2 SS mg/L 100 30 COD mg/L
194 104 BOD mg/L 100 5 PO.sub.4 mg/L 9.43 3.0 Odor ++ - Fish
Survival Nil No fatality DO mg/L 0.0 5-5.5 Bacteria (1/ml) 10.sup.9
10.sup.7 Color ++ - Pests & insects +++ - Experimental
conditions: V.sub.b = 84.0 m.sup.3; V.sub.r = 10 m.sup.3/hr;
V.sub.f = 0.0; V.sub.1 = 30 m.sup.3, batch time = 4 hr
[0099]
2TABLE 2 Continuous Biofiltration results for Pheretima elongata
cultured Soil filter Item Initial Final pH 6.96 7.11 NH.sub.4 mg/L
12.2 2.9 NO.sub.3 mg/L 7.8 3.9 Total N mg/L 11.2 3.2 SS mg/L 708 15
COD mg/L 208 83 BOD mg/L 110 5 PO.sub.4 mg/L 8.4 6.6 Odor ++ - Fish
Survival Nil No fatality DO mg/L 0.0 4.5 Bacteria (1/ml) 10.sup.9
10.sup.7 Color ++ -- Pests & insects +++ - Redox Potential, mV
50 800 V.sub.b = 84.0 m.sup.3; V.sub.r = 2.4 m.sup.3/hr; V.sub.f =
5.0 m.sup.3/h.
Example 2
[0100] A schematic of a biotower is shown in FIG. 3. The results of
the use of the biotower for renovation of water from organic waste
are given in Table 3. A Biotower is constructed using 6 vessels of
30.0L each mounted on a frame vertically one above the other. Each
vessel contains the SBT media.
[0101] In a typical experiment carbonaceous substrate
(glucose/sucrose) is charged form the top of the biotower at a
predetermined flow rate. The outlet at the bottom of the filter is
collected and analyzed for COD. Bioindicators b1 (ORP probes) were
inserted all along the tower profile and response was recorded in
data acquisition system.
[0102] The results show that very high efficiency removal of COD
can be achieved. However the overall rate of COD removal for simple
molecule (BOD) could be 0.3-0.5 kg/m.sup.3 per day. The reactivity
of the bed and earthworm activity all along the depth found to be
uniform. In view of the multiple stages the water quality
parameters (BOD, COD, Nitrogen, suspended Solids, color, odor,
bacteria, virus) as required can be achieved.
3TABLE 3 Results of Biotower studies using 6 stage Pheretima
elongata cultured biotower Feed rate, COD inlet COD outlet RUN
ml/min. mg/L mg/L pH feed pH out BT1 45 282 2-3 6.8 7.1 BT2 45 668
6-17 7.1 7.5
Example 3
[0103] In these experiments a mineral source is contacted with the
water from the organic waste containing the pollutant (natural
& synthetic) in conical flask. The flask is mounted on a shaker
incubator to facilitate solid-liquid contact typically for 30 min.
The temperature is maintained at 28-30.degree. C. The pollutant
level in the liquid is determined by filtering off the solids from
the sample reaction mixture. Results of sewage water contacted with
mineral source are given below. Table 4 shows the effect of mineral
source in wastewater renovation. The results show that use of
mineral source in the range 250 mg/L brings about substantial
removal of pollution level in the wastewater.
4TABLE 4 Effect of additives for COD and nitrate removal Mineral
Powder* SUBSTRATES Additive mg/L Initial mg/L Final mg/L Nitrates
(as sewage) 200 107 75.9 Nitrates (KNO.sub.3) 66 105 74 COD (as
sewage) 200 191 112 *Mineral source powder containing silica
(20-30% Si), alumina (6-8% Al), iron (1-6% Fe), Potassium (2-8% K),
calcium (2-10%), Mg (1-3%)
Example 4
[0104] 100 kg of cow dung is taken. It is mixed with 100 kg of
mineral source at ambient temperature of 25-28.degree. C. Free
Moisture content of the prepared mix is around 25%. The mix is
incubated in an earthworm-cultured bed for 7 days and moisture is
maintained by sprinkling water. During the seven-day process the
mix is monitored for pH and pest incidence. At the end of 7 days it
is sun dried and sieved to less than 500 microns.
[0105] The final product obtained is of the following
characteristics: (1) fragrant soil smell while free moisture is
maintained out around 10-15% (2) free flowing, (3) no pests and
insects, (4) contains about 10-15% organics, about 65-75% minerals
and 10-15% moisture. The soil product used as medium to grow potted
plant shows vigorous plant growth indicating that the soil product
is capable of being used as correction to eroded soils to restore
productivity.
Example 5
[0106] 100 kg of fresh food waste is taken and mixed with 50 kg of
mineral source, 100 g of bacterial culture and is processed in a
geophagus earthworm cultured green space. Moisture is maintained at
20 percent and processing continued for 14 weeks.
[0107] The final product has the following characterisations: (1)
fragrant soil smell while free moisture is maintained at 15-20%,
(2) free flowing, (3) no pests and insects, (4) contain about 5-10%
organics, about 70-85% mineral and about 10-15% moisture. The
culture grade product used as input to grow potted plants shows
vigorous plant growth indicating that the culture grade product is
capable of being used as correction to eroded soils to restore
productivity.
Example 6
[0108] An organic waste processing plant to handle 16 tons per day
of market organic waste is described. An area of 10800 m.sup.2 is
earmarked. The space is organized as 20 loading bays each of 30 M
(8.0 m base-10.0 m top).times.1.0 m deep. The green spaces are
constructed on ground as ridges of size 30 M (2.0 m base-4.0 m
top).times.1.0 m high. The green space serves as the reservoir of
culture required for the process. Suitable space for storage of
additives and product are also provided. The entire space is
cultured with geophagus earthworms. Suitable green plants to house
the earthworm culture are planted on the ridges.
[0109] During loading, the waste is spread over the loading area.
Mineral source in the range 0.3-0.6 kg/kg waste, soil in the range
0.1-0.2 kg./kg waste; bacterial culture 0.01 kg/kg waste, natural
phosphates if required 0.02-0.05 kg/kg waste are sprinkled.
Moisture is maintained at 20-30% on the soil. The loaded area is
periodically turned manually. This may also be turned mechanically
by a tractor and lumps are mechanically shredded.
[0110] A 14 weeks schedule for loading and as well 14 weeks
schedule for curing/harvesting is engaged. During harvesting the
material from the curing bays are dug out, screened and bagged. For
the batches with any abnormal bioindicators more mineral powder is
sprinkled and the material turned and allowed to process further
for 2-3 days. The fertilizer grade product formed has moisture of
15-20%, 20-30% organic, 50-65% minerals and is free flowing.
Example 7
[0111] Hospital organic wastes are taken directly to geophagous
earthworm cultured green space. The wastes are spread carefully on
the processing area protected suitably via impervious lining. Soil
in amount of 0.3-0.6 kg per kg waste and mineral powder@0.3-0.6 kg
per kg waste are sprinkled. Loading is continued till the pit is
full typically in 4 weeks. The processing is continued for 48
weeks. During processing the moisture in the pits was maintained at
30-40%.
[0112] The processed material is turned periodically.
Non-biodegradables are removed and destroyed. The soil is ploughed,
mixed with dry leaves and kerosene. The whole mass is ignited and
allowed to burn. The next batch is then taken.
[0113] Analytical Methods:
[0114] Analytical Methods engaged for the analysis of COD, BOD,
Ammonium Nitrogen, suspended solids, and color have been adopted
from "Standard Methods of Water and Wastewater Analysis (APHA,
Standard Methods for Examination of Water and Wastewater", American
Public Health association, 18.sup.th edition, Washington, 1992).
Manual for Photometer SQ 118, E-Merck (Germany) 1997; Standard
Methods of Water Analysis Handbook, Hach, USA (1997).
[0115] Bioindicators such as fish, mosquito, rats and flies have
been identified visually and reported as our visual
observation.
[0116] Bioindicators as a tool for assessment of pollution index of
environment has been adopted from "Aquatic Chemistry" by Stumm,
Werner; Morgan, J. J. in Aquatic Chemistry--an introduction
emphasizing equilibrium in natural waters, 2.sup.nd edition, Wiley
Interscience, NY (1981).
[0117] Bioindicators b1 are used at various stages of the processes
to test for any toxic materials produced. Bioindicators such as
fish, mosquito, rats, flies have been identified visually and
reported as our visual observation. Bioindicators as a tool for
assessment of pollution index of environment has been adopted from
`Aquatic Chemistry` (by Stumm, Werner; Morgan, J. J.; "Aquatic
Chemistry--an introduction emphasizing equillibria in natural
waters," 2.sup.nd edition, Wiley Interscience, NY, 1981).
[0118] Tests for microbiological indicators like Coliform
organisms, Staphylococci, Kleibsella pneumonie, Salmonella,
Shigella, Entamoeba hystolytica, Polio virus, Hepatitis virus were
carried out using methodology from Standard Methods of Water and
Wastewater Analysis ("APHA--Standard Methods for Examination of
Water and Wastewater," American Public Health Association,
18.sup.th edition, Washington, 1992).
[0119] The performance of the different source of organic waste
were noted as detailed under Table 5.
5TABLE 5 Performance of different sources of organic waste Market-
Source Cow dung Food Waste Vegetables Protein Waste kg wet 100 300
200 200 organic Additive B kg 100 30 50 40 Additive L kg -- 10 - 10
Additive H kg -- 10 - - PH 6.8-7.5 6.8-7.5 6.8-7.5 6.8-7.5 Moisture
in product 10-15 10-15 10-15 10-15 (%) Batch Time days 7 200 100
100 Product kg 150 60 100 100 Conditioner Product Soil Culture
Fertiliser Fertiliser type Residues Nil Nil Nil Nil Pests on
Product Nil Nil Nil Nil Shelf life of Product 12+ 12+ 12+ 12+
(months) B-silica rich mineral L-relatively low silica mineral
H-iron rich mineral
[0120] As would be evident from the results under Table 5, the
material produced following the process of this invention find
applications as a variety of soil conditioning agents of fertilizer
grade, culture grade and soil grade. Further the products obtained
are free of any harmful residues and have desirable shelf life.
Equally important is the fact that the products are substantially
free of toxic substances, which make it environment friendly and
safe for use.
[0121] The redox potential of 900 mV indicates high oxygen
availability and hence is a very healthy environment wherein the
pathogen survival is unlikely. The nutrients in the waste get fixed
in biomass and are internally recycled. The organic loading being
small the nutrient levels in soil do not change much. Overall the
results show that the procedure can handle hospital waste
effectively.
[0122] Table 6 summarizes the results of treatment of hospital
organic waste prepared as in Example 8. The results show that the
hospital organic waste treated soil has characteristics similar to
those of the control soil. Pathogens are not detected both in
control soil and in treated samples.
6TABLE 6 Total N and P levels in Soil after Hospital Waste (HW)
Process Total E.sub.h Bacteria per Item (mV) N (%) P (%) g soil
Remarks Control Soil 900 0.01 0.001 10.sup.7-10.sup.8 * Soil after
12 900 0.01 0.001 10.sup.7-10.sup.8 * months HW HW Soil after 900
0.01-0.005 0.001 10.sup.7-10.sup.8 * curing in Flower bed HW Soil
after 900 0.01-0.005 0.001 Very small * heat treatment HW--Hospital
Waste; *--Pathogens: not detected; E.sub.h--Redox potential-high
value indicates healthy soil
[0123] The SBT process disclosed in this invention thus provides a
cost effective and simple solution to the problem of organic waste
management without creating any toxic wastes or issues of waste
disposal. The product produced from this process is environment
friendly and can be used as a soil-conditioning agent for diverse
applications. It also provides a method for the effective
utilisation of the recoverable bio-energy to produce products in
high yields, and also offers avenues to systematically and cost
effectively treat organic wastes from various sources such as
hospitals, restaurants, markets, food, fermentation,
agro-industries etc.
[0124] Overall this process for soil conditioning makes it possible
to enhance the soil productivity in a cost effective manner in a
global perspective
[0125] All publications and patent applications cited in this
specification are herein incorporated by reference as if each
individual publication or patent application were specifically and
individually indicated to be incorporated by reference.
[0126] Although the foregoing invention has been described in some
detail by way of illustration and example for purposes of clarity
of understanding, it will be readily apparent to those of ordinary
skill in the art in light of the teachings of this invention that
certain changes and modifications may be made thereto without
departing from the spirit or scope of the appended claims.
* * * * *